Editing Cardinal mark

{{short description|Sea mark indicating where safe water is near to a hazard}}
[[File:Cardinal Marks.gif|right|300px|thumb|Diagram of cardinal marks as seen during the day, with their light patterns.  The lights shown here are configured as "Quick".]]
A '''cardinal mark''' is a [[sea mark]] (a [[buoy]] or other floating or fixed structure) commonly used in maritime [[pilotage]] to indicate the position of a hazard and the direction of safe water.

Cardinal marks indicate the direction of safety as a [[cardinal directions|cardinal]] ([[compass]]) direction ([[north]], [[east]], [[south]] or [[west]]) relative to the mark. This makes them meaningful regardless of the direction or position of the approaching vessel, in contrast to the (perhaps better-known) [[lateral mark]] system.

== Characteristics ==
The characteristics and meanings of cardinal marks are as defined by the [[International Association of Lighthouse Authorities]].

A cardinal mark indicates one of the four compass directions by:

* the direction of its two conical top-marks, which can both point up, indicating north; down, indicating south; towards each other, indicating west; or away from each other, indicating east
* its distinctive pattern of black and yellow stripes, which follows the orientation of the cones - the black stripe is in the position pointed to by the cones (e.g. at the top for a north cardinal, in the middle for a west cardinal)
* optionally, its distinctive sequence of flashing light, which consists of a sequence of quick or very quick flashes whose number gives the [[clockface]] position which corresponds to the direction of the cardinal (e.g. three for an east cardinal, nine for a west; north has continuous flashes, and south may be augmented with a long flash, to help distinguish it from a west in difficult conditions)

{| class=wikitable
|+ Summary of mark characteristics{{sfn|IALA|2010|p=14}}
! Characteristic !! North !! South !! East !! West
|-
! Topmark
| ▲<br/>▲<br/>Both cones point upwards || ▼<br/>▼<br/>Both cones point downwards || ▲<br/>▼<br/>Cones point away from each other || ▼<br/>▲<br/>cones point towards each other
|-
! Colour
| Black above yellow || Yellow above black || Yellow horizontal band on a black body || Black horizontal band on a yellow body
|-
! Light (if fitted)
| Continuous flashes || 6 quick flashes + 1 long flash || 3 flashes || 9 flashes
|}

Either a quick or a very quick sequence of light flashes may be used; the choice allows for two similar nearby marks to be uniquely identified by their lights.

A cardinal mark may be used to accomplish the following:

*Indicate that the deepest water is an area on the named side of the mark
*Indicate the safe side on which to pass a danger
*Draw attention to a feature in a channel, such as a bend, junction, branch, or end of a shoal
*Draw attention to a new danger such as a grounded ship. In such cases two equal marks are often placed together to indicate that it's a newly marked danger and is not yet printed in official charts.

Other uses:

*Sometimes a Cardinal Mark can be used instead of a [[Special mark]] to indicate a spoil ground, or an outfall pipe for example. A few examples can be seen on the South Coast of [[England]] and in Northern [[France]].

==Mnemonics==
The north and south topmarks are self-explanatory (both cones pointing up, or both pointing down).  Remembering the east and west marks can be more of a problem.

The most natural way to distinguish the topmarks for east and west is to "follow the Sun"—the top cone indicates the direction the Sun would appear to move when visible in the part of the sky that corresponds to the mark's communicated direction, while the bottom cone indicates likewise for the Sun's reflection on a calm ocean surface.  So when a topmark consists of two cones pointing ''away'' from each other, this should suggest the Sun moving ''away'' from its reflection on a calm ocean surface, which happens when the Sun [[sunrise|''rises'']], and a ''rising'' Sun is visible to the ''east''.  Likewise, a topmark with two cones pointing ''toward'' each other should suggest a [[sunset|''setting'']] Sun, which is visible to the ''west''.{{sfn|Sanders|2018}}

Other mnemonics have been devised for the east and west marks in case the mnemonic that uses the Sun is difficult to grasp.  For example:
* East looks like an '''E'''aster '''e'''gg.  The western mark has a pinched waist: "'''W'''estern '''w'''omen have '''w'''asp '''w'''aists".{{sfn|Noice|2013|p=130}}
* East looks like a classical letter E/epsilon.  The western mark looks like a "W" on its side, or "'''W'''est '''w'''inds '''w'''ool" (looks like a [[bobbin]]){{sfn|Cunliffe|2016|p=34}}
* East is larger around the middle: "'''E'''quatorially '''e'''nlarged".  West is a '''w'''oman's '''w'''aist.{{sfn|RYA|1985|loc=plates between pp 72 and 73}}
* West looks like a wine glass with the narrow stem and wide top and bottom.

The colours can be remembered this way:  ''The two conical top-marks always point to black''.
*If the top-marks point to the top, black is at the top.
*If the top-marks point to the bottom, black is at the bottom.
*If the top-marks point to the middle, black is at the middle.
*If the top-marks point to the outside, black is at the outside.

==Gallery==
<gallery>
Image:Knoll-North-Cardinal-Canthusus.JPG|Knoll North Cardinal
Image:Stavros_S_Niarchos.jpg|The 'East Bramble' East Cardinal Mark helps the ''Stavros S Niarchos'' navigate safely in the Solent, August 2008
Image:4 cardinals.jpg|All four types of cardinal mark used in Nanaimo Harbour to warn of an old concrete base.
Image:Cardinal mark (east) in ice in front of South Harbor Helsinki Finland.jpg|A light buoying cardinal mark (east) in pressure of ice in front of Helsinki, Finland in winter. Notice that topmark is not used on a buoy that is subjected to ripping by movements of ice.
File:South cardinal buoy off St Mawes (4950686323).jpg | A south cardinal mark buoy off St Mawes, UK
</gallery>

==See also==
{{Portal|Transport}}
*{{annotated link|Navigation}}
*{{annotated link|Lateral mark}}
*{{annotated link|Safe water mark}}
*{{annotated link|Isolated danger mark}}
*{{annotated link|Special mark}}
*{{annotated link|Emergency wreck buoy}}

==References==
{{reflist}}
==Citations==
{{Commons category|Cardinal marks}}
*{{ Citation
  | last = Cunliffe
  | first = Tom
  | title = The complete day skipper
  | publisher = Adlard Coles nautical (an imprint of Bloomsbury)
  | year = 2016
  | orig-year = 2002
  | edition = fifth
  | isbn = 978-1-4729-2416-2
}}
*{{Citation
  | author       = IALA
  | url          = http://www.iala-aism.org/web/pages/publications/docpdf/mbsenpdf/mbs6to9.pdf
  | title        = Cardinal Marks
  | publisher    = IALA
  | access-date  = 2010-06-01
  | archive-url  = https://web.archive.org/web/20071214074824/http://www.iala-aism.org/web/pages/publications/docpdf/mbsenpdf/mbs6to9.pdf
  | archive-date = 2007-12-14
  | url-status   = dead
}}
*{{ Citation
  | author = IALA
  | title = Maritime buoyage system and other aids to navigation
  | publisher = IALA (International association of maritime aids to navigation and lighthouse authorities)
  | year = 2010
  | url = https://www.irishlights.ie/media/11141/IALA-MBS.pdf
  | accessdate = 11 August 2019
}}
*{{ Citation
  | last = Noice
  | first = Alison
  | title = Day skipper for sail & power
  | publisher = Adlard Coles nautical (an imprint of Bloomsbury)
  | year = 2013
  | orig-year = 2007
  | edition = second
  | isbn = 978-1-4081-9310-5
}}
*{{ Citation
  | author = RYA
  | title = Navigation, an RYA manual
  | date = 1985
  | edition = second
  | orig-year = 1981
  | isbn = 0-7153-8631-X
  | publisher = David & Charles
  | place = Newton Abbot
}}
*{{ Citation
  | last = Sanders
  | first = John
  | title = Cardinal Marks
  | date = 2018
  | website = Boatschool
  | url = https://www.boatschool.com.au/cardinal-marks/
  | accessdate = 15 September 2020
}}
{{DEFAULTSORT:Cardinal Mark}}
[[Category:Navigational buoys]]
[[Category:Marine navigation]]